Blown Head gasket?

[king_argos]

Here's the scoop. 2000 ranger 4x4 4.0 v6 145000 miles.
Had a serious coolant leak behind the pass side head and was blowing coolant out the exhaust. Since it was obviously getting into the cylinder, we pulled that head and also pulled the other head since we were that deep anyway. The heads look fine and can't really see anything obviously wrong with the gaskets to indicate where the coolant was getting by. My question is what steps to take next? This is a secondary vehicle for me, and it has a lot of miles on it, so I don't really want to spend alot. What are my chances of success if I just throw it back together with new gaskets? Any thoughts or advice would be appreciated and thanks in advance.

 

[Downey]

do you have the OHV or SOHC motor?

but if you are doing the work yourself i say do it. i have 271,000 miles on my 4.0 ohv these motors are good and strong

 

[UrbanRedneckKid]

Send the heads to get magnifluxed(aka checked for cracks).
While having them checked, have new stem seals put in and the valve seats reground.

The coolant leak at the back of the head, and in the combustion chamber was probably the intake gasket, though it doesn't matter now, the heads are already off. You are right at what seems to be the average mileage for the intake gaskets.

Also I highly highly recommend OEM Ford intake gaskets, and valve cover gaskets.

And you need new head bolts, the 4.0 headbolts cannot be reused.

 

[exbass94]

do you have the OHV or SOHC motor?

2000 Ranger = OHV

 

[mosher41]

these heads are known for cracking, have them hot tanked, pressure checked and planed. I just did this to mine and the machine shop were suprised they were not cracked. Upper gasket set and bolt set about 260.00 at advance auto.

 

[modelageek]

what does it cost to have the heads mangaflexed and rebuilt?

 

[mosher41]

it cost me 160.00 to have them tanked, pressure checked and planed.
I did the valve work myself

it may be a little more, i get a good break from the shop i use

 

[Big Jim M]

Give is a biy more information.

Here's the scoop. 2000 ranger 4x4 4.0 v6 145000 miles.
Had a serious coolant leak behind the pass side head and was blowing coolant out the exhaust. Since it was obviously getting into the cylinder, we pulled that head and also pulled the other head since we were that deep anyway. The heads look fine and can't really see anything obviously wrong with the gaskets to indicate where the coolant was getting by. My question is what steps to take next? This is a secondary vehicle for me, and it has a lot of miles on it, so I don't really want to spend alot. What are my chances of success if I just throw it back together with new gaskets? Any thoughts or advice would be appreciated and thanks in advance.

Tell us about the coolant coming out the exhaust.
When it come out?
Then tell us about the external leak.
How much was leaking?

I'm thinking you pulled heads that didn't need pulling. I'm thinking you saw condensation from the tail pipe and pulled GOOD heads off the engine.
Could the external leak of coolant have come from other than the head?
Big JIm

 

[king_argos]

Not condensation....Lots of white vapor...wet ur hand quick..smelled and tasted like coolant. The leak was spraying against the firewall, pass side. Felt like it was coming from under the head, couldn't really see it. It was shooting out with pressure even before the coolant got too hot to hold my hand in the stream. Enough coming out to run down the driveway. I'd guess at least close to a half gallon, before the temp got high enough that i needed to shut it down. Less than 5 minutes. The problem started quick and got worse in a hurry. My first thought was a soft plug, but the coolant was coming out below the one on the back of the head. Any way....shut it down, let it cool down overnight and tore it apart. The heads are now at the shop for testing and cleaning. Surfacing if they need it. Cylinder walls are in great shape, still see the hone marks and no ridge to speak of. The motor wasn't using oil before and no probs to speak of. Pretty surprised at how clean the heads and topend of motor looked. I'll update with what the shop finds out on the heads. If they look good, I'm going to reinstall and see how it goes. Might replace the stem seals while the heads are out. Have to see if I can come up with a valve spring compressor. Thanks again for the input.

 

[mosher41]

King,
you probably already know this, when reassembling be sure to silicone the corners of the intake gaskets at the spot where the heads and intake meet...in fact we dont even use the little S-shaped rubber gaskets at all and just put a nice bead of Black permtex along both front and rear surfaces. Make sure both are very clean too. A garage did my fathers truck and it leaked oil and water, I had to re do the intake gaskets.

Be sure and change the oil too, anti freeze is BAD BAD for the bearings

 

[king_argos]

Got a call from the shop. The heads have no cracks but were warped. One was .004 out. The other was .012 out. Seems like I saw where these heads could only have .010 removed. He said he would look it up, but even then a shim could be used. Total cost per head is 15 to hot tank, 18 to to check for cracks, 40 for surfacing. Does that sound bout right?

He did say he thought that the heads were in really good shape. Other than the warp. If it were his he would just replace the seals and put them back in after planing.

Opinions welcome